Smart contracts are widely used in dApps and blockchain platforms. There are several vulnerabilities and attacks to which smart contracts are susceptible, leading to a significant risk in terms of both financial and operational risks. The paper proposes an all-inclusive security framework for preventing common vulnerabilities and attacks against smart contracts. The proposed framework integrates multiple security protocols, which include static code analysis, formal verification, security auditing, dynamic testing, and runtime monitoring. Using MythX, Slither, and Tenderly as vulnerability analysis tools for some smart contracts in terms of reentrancy, integer overflows, issues in gas limit, and access control vulnerabilities, the framework’s detection and prevention ratio is highly dominant enough that it can significantly decrease the success percentage of simulated attacks with reentrancy and overflow exploitation. Results for performance measurement clearly show that there is no great overhead in consumption and execution in gas, keeping this framework really handy for applications on the blockchains. Results from external security audits and runtime monitoring further prove robustness due to the outcomes. This paper makes a big critical contribution towards improving the security of smart contracts and proposes real-world solutions towards the mitigation of risk in blockchain-based applications.